The review in the forum is quoted at other photography areas on the internet. For example this one:
Pentax K3 indepth review @ Pentaxfrums - Steve's Digicams Forums
Where it flat out says Pentax auto focus lags behind Nikon. It does not say that the test was performed using a system from Nikon where just the lens costs about the same as the Pentax Camera and lens, it doesn't say that the two systems compared are vastly different in price. It just says that Pentax AF lags Nikon AF based upon the review in the Pentax Forum.
The review did not properly test one camera's auto focus versus another.
I still feel the existing review in the AF section as performed and as written is a disservice.
am venturing a guess that if the Nikon 7100 was used and the AF test as described were performed using RAW images then the Nikon would rank below the Pentax untis in the test, even with the spiffy $2300 lens. If that result were the case would it be proper to say that Nikon AF lagged Pentax - absolutely not.
I feel the test can only conclude that the Pentax system as tested performs below the Nikon system as tested.
The conclusions drawn in this test are being interpreted incorrectly because the test was improper in its format except to test the Pentax K-3 equipped with the 60-250 versus the Nikon D610 equipped with the 70-200.
As I stated elsewhere I feel the forum review and test of auto focus should be rewritten or expanded in the auto-focus area to compare apples vs apples.
I am guessing if the Nikon 7100 were used in a test using a common lens - thereby comparing one camera versus another - the K-3 would outperform the Nikon, probably by a very wide margin in raw.
The existing review gives people looking at making camera decisions a incorrect comparison. The only valid comparison is for a person who is going to decide should I buy a Pentax K-3 with a Pentax 60-250 or should I buy the Nikon D610 with the Nikon 70-200 f2.8. To me that is like deciding if I should by a Nissan Altima or a Chevrolet Corvette. If you want a Corvette you should buy it if you can afford the price. If you don;'t have that much money to spend on another car then a comparison of a Corvette against an Altima provides information of little relevance.
The intent of the test was good, the execution was probably done quickly to get the review published, the conclusion is not warranted by this test.